Spring construction



Feb. 16, 1943. T, SARK SPRING CONSTRUCTION Filed Jan. 6, 1941 PatentedFeb. 16, 1943 UNITED sr SPRING CONSTRUCTION Ward T. Sark, Oak Park,Ill., assgnor to Haggard and Marcusson Co., Chicago, Ill., a corporationf Illinois Application January 6, 1941, serial No. 373,239

4 Claims.

My invention relates to spring means for use in beds, couches, glidersand the like and particularly to a construction in which e, flexiblestructure is arranged over the top of the spaced spring elements.

In a construction such as described, it is common to employ a series offlat, exible strips overlying the tops of adjacent springs and extendingbetween the border, the strips being joined to the border by helicalsprings placed under a degree of tension. The objection to such anarrangement, even where a. border member of substantial cross sectionalarea is provided, is that the constant pull of the tension members forthe strips tends to bow or bend inward the border, rendering the springobjectionable both in the point of sale and use. l

Such bowing and distortion of the border member occurs also duringhandling, and so-called stabilizers are commonly provided forstrengthening or reinforcing the borders and preventing side sway.

I have accomplished the desired result of avoiding distortion of theborder, even when one of small cross sectional area is used, and ofstabilizing the structure by the use of very simple and inexpensivemeans. with a resulting saving, not only in weight but in cost ofconstruction.

The invention will be more readily understood by reference to theaccompanying drawing; in which:

Fig. 1 is a plan view of a portion of a bed spring to which myimprovement has been applied; and

Fig. 2 is a sectional view somewhat enlarged, the view being taken onthe line 2-2 of Fig. 1.

The spring construction illustrated in Fig. l comprises a frame I0 withthe usual cross girders on which the side springs Il and intermediatesprings I2 are mounted. The respective springs are joined by thediagonally arranged helicals I3, all of the foregoing being commonconstruction.

The side springs II are connected to a border rod I4 which extendsentirely around the spring structure, the top coil of the springs IIbeing seated in a kerf milled into the border, and the metal of the rodbeing pinched over the wire of the spring to hold it in place, all asshown at I5in Fig.2.

Flexible flat strips Iii-I1 extend transversely and longitudinally ofthe structure and overlie each other at the axis of each of theintermediate springs. A helical spring I8 is connected through a wireclip I9 to the border, the clip being bent around the top coil of theside springs II at its point of engagement with the border, and theopposite end of the helical being hooked to the strip. However, thestrips at their end portions are reinforced by means of a short section2U which is welded or riveted thereto, the section being oiiset as ati2| to provide an open space or slot 22. The outer end of the shortsection is perforated to receive the hook of the helical I8. The partsareso dimensioned that in normal position all the tension exerted by thehelical I8 is exerted against the upper turn of the outer spring II, theportion of the flat strip between the outer coils, being withouttension. It should be understood that, for all practical purposes, thetop coil of the border spring is laterally incompressible by the forceof the helical I8. The said top coil is of such rigidity that theinitial tension of the helical has no noticeable effect toward changingthe shape of the said top coil. When a load is imposed on the springthat would tend to elongate the strips and consequently the helicals I8,the strips may freely move inwardly because of the slot 22, and thusexert an additional pullon the helicals at the ends of the strips. Thusthe only time that any pull is exerted tending to bend inward the bordermember is when a load is imposed on the spring. At all other timesv thetension of the helicals is neutralized so far as the border isconcerned.

The construction described brings about the other important result; thatis, the stabilizing of the structure. In view of the fact that the outeredges of the side springs are firmly held against rotation, the holdingof the inner edges of the outer springs against rotation and thereinforcing of the strips at their ends brings about the surprisingresult of stabilizing of the structure. This is best explained bystating that since the top coil of the outer spring cannot benddownward, at its inner portion, any inward thrust exerted on the borderis transmitted directly along the axis of the strip. Although the stripsare flexible, they are held against flexure at closely spaced points andthus the thrust is in effect, transmitted entirely across the structure.In this manner I am able to avoid more expensive and complicatedstabilizing structures and thereby to produce a lighter and lessexpensive spring.

It will be understood that the opposite side of the spring is identicalwith that shown. Further, that while I have shown the springneutralizing device as applied to all of the flat strips composing theplatform or upper structure, I may prefer to apply the feature: only tothe strips at the middle of the structure, omitting it at the ends. Itwill be understood also that the desired result of neutralizing the pullof the transverse helical springs by exerting the normal pull againstthe top coil of the outside springs in a specific manner may beaccomplished in other ways than that shown, and I do not wish to belimited except as indicated in the appended claims.

I claim:

1. In means for preventing the bending of the border of a springstructure, and for stabilizing said structure, a series of spacedsprings,the top coils of a plurality of the outer springs of which areimmovably fixed to said border, at strips overlying the springs andextending between the members constituting the respective sides of theborder, helical springs connecting the ends of the strips to the border,the strips having a double thickness at their ends between which the topcoil of the outer springs is conned, said strips providing stopsabutting the top coil of the outer springs at a point diametricallyopposite the point of engagement of said top coil with the border,whereby the initial tension of said helical springs is exerted againstsaid top coil and is thus neutralized in relation to the border.

2. In means for preventing the bending of the border of a springstructure and for stabilizing said structure, a series of spacedsprings, the top coils of a plurality of the outer springs of which areimmovably xed to said border, flat strips overlying the springs andextending between the members constituting the respective sides of theborder, helical springs connecting the ends of the strips to the border,said strips being stiffened at their ends and having a slidingconnectionl with the top coils of said outer springs so as to preventrotation of said top coils about the border and permit sliding movementof the strip, said stiiening elements providing a stop abutting the topcoils of the outer springs at a point diametrically opposite the pointof engagement of said top coils with the border whereby the initialtension of saidhelical springs is exerted against said top coils and isthus neutralized in relation to thev border. v

vr3. In means for preventing the bending of the border of a springstructure and for stabilizing e the structure, a series of spacedsprings, the top coils of a plurality of the outer springs of which areimmovably i'lxed to said border, at strips overlying the springs andextending between the members constituting the respective sides of theborder, helical springs connecting the ends of the strips to the border,the strips having a double thickness at their ends providing a slot, theinner end of which acts as a stop for the top coil of an outer spring,rat a point diametrically opposite the point of engagement of said topcoil with the border, whereby said strips may be pulled inwardly, thusplacing additional tension on said helical springs, but so that. thenormal initial tension of said helicals isexerted against said top coiland not between the border members.

4. In means for stabilizing a spring structure, a series of spacedsprings and a border, the top coils of a plurality of the outer springsbeing immovably xed to said border, at strips overlying the springs andextending between the members constituting the respective sides of theborder, and helical springs connecting the ends of the strips to theborder, said strips having means at their ends providing a slidingconnection with said top coils of said outer springs so as to preventrotation of said top coils about the border, but so as to permit slidingmovement of said strips relative to said top coils.

WARD T. SARK.

